A Nikkor for a Tenax II

[wes loder]

Wanted a wide-angle for my Tenax II. The 2.7cm f4.5 Orthometar is so rare (302 made) that I could wait a long time. But maybe there was enough room to mount a F mount Nikkor. After finding the mount for a Tenax-mount Sonnar missing its optics and a K3 ring, I made a trip to my local machine shop. They built me an adaptor. Next, I bought an old 28mm f3.5 Auto Nikkor-H, filed off the rear projecting flange and I am in business. The 2.7cm Zeiss finder for the Tenax works perfectly. A little front heavy and no rangefinder coupling, but depth-of-view works. Cheers, WES

 

[raid]

Well done, Wes. It is a 2/3 frame camera or so. Right?

 

[radi(c)al_cam]

Well done, Wes. It is a 2/3 frame camera or so. Right?

Yes, she's the 24*24mm member of the Contax family. A pity that she was discontinued.

But to an extent one could say: her stepbrother is the Robot, and her niece is the Vitessa T.

Wanted a wide-angle for my Tenax II. The 2.7cm f4.5 Orthometar is so rare (302 made) that I could wait a long time. But maybe there was enough room to mount a F mount Nikkor. After finding the mount for a Tenax-mount Sonnar missing its optics and a K3 ring, I made a trip to my local machine shop. They built me an adaptor. Next, I bought an old 28mm f3.5 Auto Nikkor-H, filed off the rear projecting flange and I am in business. The 2.7cm Zeiss finder for the Tenax works perfectly. A little front heavy and no rangefinder coupling, but depth-of-view works. Cheers, WES View attachment 104830

Marvellous!

re «front heavy»: I presume, with your Nikon-on-Tenax adapter, a Schneider 1:4/28 (for Kodak Retina) could also work with a so called «DKL» or Deckel-adapter, and would be less front heavy?

 

[wes loder]

Nikkor to Tenax

Nikkor to Tenax

The 28mm Auto Nikkor feels light until you compare it with the small original lenses for the Tenax II. I just wish it was a bit smaller. My 105mm f2.5 Auto Nikkor also mounts and works fine, but does vignette slightly. The 28 covers the 24X 24 frame. Will post pictures when I get them back from my processor. WES

 

[raid]

I have a Tenax II with the Sonnar normal lens. It may be a 40/2.
Mike Elek has a good write-up on it.
http://elekm.net/zeiss-ikon/tenax_ii/

 

[radi(c)al_cam]

I have a Tenax II with the Sonnar normal lens. It may be a 40/2.
Mike Elek has a good write-up on it.
http://elekm.net/zeiss-ikon/tenax_ii/

😀 Mike is joking when he writes:

The Tenax II is often seen these days with the f/2.8 40mm Tessar.

In fact, the Tenax II is definitely scarce, if not rare.

Perhaps one addition: not only the Vitessa T appears to be a niece of aunt Tenax II, the East German Zeiss «WERRA» family and perhaps also the Altix family appear to be related, but again, in their typical German manner, all the bayonets are incompatible, unfortunately …

 

[raid]

My example looks like a new [shiny] camera. It has been taken care of very well over the years. Lenses are simply too costly to get for the Tenax II, so what Wes has done is to breathe some new life into this camera.

 

[wes loder]

<In fact, the Tenax II is definitely scarce, if not rare.>
Simon Worsley estimates that Zeiss Ikon produced about 8500 Tenax II between 1937 and 1940. While scarcer than a Contax, this would make it a lot more common than the Super Nettel, Nettax or the pre-war Contaflex. The version with the 40mm f2 Sonnar is more common than the one with the 40mm f2.8 Tessar. The auxiliary lenses, 75 and 27, are definitely hard to find.
I have never seen the mounts for the Werra, 24X36 Altix or the Vitessa T, so cannot comment on how close they are to the Tenax II mount.

 

[radi(c)al_cam]

I have never seen the mounts for the Werra, 24X36 Altix or the Vitessa T, so cannot comment on how close they are to the Tenax II mount.

The cameras I mentioned have a large flange focal distance (e.g. Kodak Retina, Voigtländer Bessamatic, etc., are 45.7 mm), and they're built for a behind-the-lens-leaf shutter, so a lens adaptation should work.

The Vitessa T bayonet is a variant of the «DKL» mount, but annoyingly the lenses would need a different adapter, the quite common Kodak/Bessamatic-adapters for Nikon- or M42-bodies don't work.

 

[Jerevan]

That the 105 vignettes - I guess this must be some sort of mechanical vignetting since the lens definitely covers 24x24 mm.

I still haven't gotten around to sending my Tessar-equipped Tenax off for the CLA, but I am always on the look-out for a second one in good condtion, perhaps with a Sonnar. 🙂

 

[raid]

ebay right now has zero auctions for Tenax II cameras

 

[wes loder]

The cameras I mentioned have a large flange focal distance (e.g. Kodak Retina, Voigtländer Bessamatic, etc., are 45.7 mm), and they're built for a behind-the-lens-leaf shutter, so a lens adaptation should work.

Maybe-maybe-not. The Nikon F flange to focal-plane distance is 46.5mm. This was just enough. The challenge is not the mounts so much as the optical flange projections coming out of the nikkors in the back. This limited the clearance.
If one wonders as to why the Germans used so many different lens mounts, remember that Germany had strong patent laws. The camera industry constantly had to be figuring out different ways to do things because of patent restrictions. WES

 

[wes loder]

ebay right now has zero auctions for Tenax II cameras

The upcoming Tamarkin auction lists one Tenax II, plus there is one on ebay in Germany. One or two Tenax II cameras seem to show up on ebay every other month.
WES

 

[radi(c)al_cam]

Maybe-maybe-not. The Nikon F flange to focal-plane distance is 46.5mm. This was just enough. The challenge is not the mounts so much as the optical flange projections coming out of the nikkors in the back. This limited the clearance.

Of course, you're right, one has to be very careful. I know that some camera models have their leaf shutters quite deeply recessed, and others not, but I'm inexperienced regarding the Tenax II. But I found this piece of information:

An adapter ring allows to mount the Contax mount Zeiss Tessar 2.8cm f/8 on the Nettax, but this lens is not coupled to the rangefinder.

http://camera-wiki.org/wiki/Nettax

If this is true, then an adaptation of this lens on the Tenax II should also work, I suppose.

If one wonders as to why the Germans used so many different lens mounts, remember that Germany had strong patent laws. The camera industry constantly had to be figuring out different ways to do things because of patent restrictions. WES

Patents are a reason, but: why oh why did the merged Zeiss Ikon/Voigtländer company produce nine (or even more?) camera families having completely different mounts during less than a decade?

Contax, Contaflex, Contarex, Icarex, Icarex TM, Contaflex 126, Prominent, Bessamatic/Ultramatic, Vitessa T…?

 

[sevo]

Patents are a reason, but: why oh why did the merged Zeiss Ikon/Voigtländer company produce nine (or even more?) camera families having completely different mounts during less than a decade?

Contax, Contaflex, Contarex, Icarex, Icarex TM, Contaflex 126, Prominent, Bessamatic/Ultramatic, Vitessa T…?

Well, that list spans actually more like four decades of mount design, from the Contax I to the Rollei era. And neither the Contax nor the Prominent were still in development at the time of the merger (the only - joint - rangefinder designed after the merger was a never produced Contax IV prototype with Ultron lens). Corporate introspection probably is to blame for the SLR mess - they ignored all competition outside their own house, and designed cameras according to their corporate layout of multiple branches with plenty of internal animosities. They started out into SLRs with the intention to be more complex than the Contax D they had left behind in the GDR, invented separate pro (FP) and consumer (leaf shutter) lines (the latter presumably as they owned the two biggest leaf shutter makers in the Western world), added a third line through Voigtländer, and spun down to a fourth and fifth in their last attempts to modernise and merge both consumer lines to catch up with the Japanese competition - and finally got picked up by Rollei, who had just released a more modern SLR with yet another mount...

 

[radi(c)al_cam]

Well, that list spans actually more like four decades of mount design, from the Contax I to the Rollei era. […]

This is true of course, but I meant: AFAIK, models of all these very different systems — of basically one (1956) and the same (after 1965 at least) company — were purchasable as «new» during say 1959–69, and this abundance of lens mounts resp. the incompatibility issues were certainly VERY annoying for a lot of customers.

But back to topic:

Dear WES,
have you tried shorter lengths than your 28mm Nikkor?
I've read about a very strange huge retrofocus 24mm lens made for the Prominent (IIRC prototypes only, and bizarrely: with mirror box!).
Hence I guess that basically shorter wide angles can work with a behind-the-lens leaf shutter.

 

[jarski]

kudos to OP for his Nikkor Tenax.

here's my 21st century "Tenax" 😀

 

[sevo]

This is true of course, but I meant: AFAIK, models of all these very different systems — of basically one (1956) and the same (after 1965 at least) company — were purchasable as «new» during say 1959–69, and this abundance of lens mounts resp. the incompatibility issues were certainly VERY annoying for a lot of customers.

Well, they were a major handicap for Zeiss Ikon. But as far as customers were concerned, they probably were happy that ZI were still supplying that many already obsoleted mount systems with cameras and lenses. The mess of ZI systems is more due to ZI never introducing anything attractive enough to compete with the Japanese - as they had no new system that grew enough market share to abandon the old ones, they had to hold on.

 

[radi(c)al_cam]

kudos to OP for his Nikkor Tenax.

here's my 21st century "Tenax" 😀

Excellent! Is that a custom-made adapter, or did you buy it somewhere?

 

[Dralowid]

Does anyone have an old Cooke and Perkins catalogue? I know they made the Contax 50mm) to LTM adaptor for many years but wonder if they had a go at any of the others?